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1.
J Acoust Soc Am ; 153(3): 1943, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37002072

ABSTRACT

An acoustic absorption structure of a double-layer porous metal material with air layers is proposed. The Johnson-Champoux-Allard (JCA) model combined with the transfer matrix method (TMM) was used to establish the theoretical calculation model of the sound absorption coefficient (SAC). Meanwhile, the SAC between 500 and 6300 Hz were measured with an impedance tube. The errors between the theoretical and experimental values were compared to illustrate the good predictability of the theoretical model within the inverse estimations of the transport properties. The effects of the material placement order, material thickness, and cavity depth on the sound absorption performance from 200 to 5000 Hz were analyzed using the theoretical model. Further, a multi-objective function genetic algorithm was used to optimize the porous material's thickness and SAC to obtain an acoustic structure with a smaller thickness and higher sound absorption. A series of optimal solutions were obtained for acoustic structures with a total thickness of less than 70 mm. When the total thickness of the foam metal was 33.57 mm, the average SAC reached 0.853, which was significantly lower than the total thickness of the previous experiments. The multi-objective function genetic algorithm can provide a reliable solution for the optimal design of most sound-absorbing structures.

2.
Nanoscale ; 15(5): 2316-2322, 2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36636988

ABSTRACT

Elucidating the coordination structures and assembling modes of atomically precise metal nanoclusters (NCs) remains a hot topic as it gives answers to the underlying mechanism of nanomaterials and bulk materials in terms of structure-property relationships. Here we report a novel silver-copper alloy NC featuring rich alkynyl-metal coordination modes and unique SbF6- assembling structures. The NC, with the composition of [Ag18Cu8(dppp)4(tBu-C6H4CC)22](SbF6)4 (dppp = 1,3-bis(diphenylphosphino)-propane), was prepared by a stepwise synthetic approach. Single-crystal X-ray diffraction analysis revealed that such a NC featured a staircase-like Ag18Cu8 kernel, which was protected by hybrid alkynyl and dppp ligands in diverse coordination structures and multiple environments. The structural analysis also revealed the unique function of SbF6- in inducing the assembly of cluster moieties, highlighting the importance of counterions in assembling nanomolecules. The diverse coordination structures of the protective ligands with metal ions and the indispensable roles of counterions in assembling the cluster moieties have also been supported by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) studies, making it a model system to showcase the uniqueness of atomically precise metal NCs in illustrating the coordination chemistry of nanomaterials and bulk materials at the molecular level.

3.
Dalton Trans ; 52(1): 52-57, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36453230

ABSTRACT

A novel alkynyl-stabilized silver-copper alloy nanocluster with the composition of [Ag13-xCu6+x(tBuC6H4CC)14(PPh3)6](SbF6)3 was prepared by the (PPh3)2CuBH4-mediated reduction approach. The nanocluster features a centred disordered-octahedral Ag7Cu6 kernel, which is protected by hybrid alkynyl and triphenylphosphine ligands. Structural comparison of this two-electron nanocluster with other alkynyl-capped Ag/Cu ones suggested that the structure of alkynyl ligands played an important role in dictating the structures of the resulting nanoclusters. The title cluster showed high performance in the catalytic hydrogenation of 4-nitrophenol, indicative of the bright future of cluster-based catalysts.

4.
Dalton Trans ; 51(17): 6682-6686, 2022 May 03.
Article in English | MEDLINE | ID: mdl-35411897

ABSTRACT

The one-dimensional coordination polymers {[CuII(hfac)2]3(m-BNN)}n·nCH2Cl2 (1·CH2Cl2, P1̄) and {[CuII(hfac)2]3(m-BNN)}n (1', P2/n), hfac = hexafluoroacetylacetonate and m-BNN = meta-phenylene bis(nitronyl-nitroxide), were obtained from CH2Cl2 and CHCl3, respectively. 1·CH2Cl2 is transformed to 1 at 335 K. Their magnetic susceptibilities differ in both magnitude and temperature dependence behavior. 1 and 1' undergo a ferroelastic-like phase transition at 110 K and an unidentified one at 37 K. There is a subtle long relaxation of this ferroelastic-like ordered state.

5.
ACS Omega ; 7(12): 10022-10028, 2022 Mar 29.
Article in English | MEDLINE | ID: mdl-35382344

ABSTRACT

Two novel cocrystal MnII compounds were successfully synthesized. The composition of two kinds crystals correspond to [Mn(hfac)2La 2·Mn(hfac)2La(H2O)·Mn(hfac)2(H2O)2] (1) and [Mn(hfac)2Lb 2·Mn(hfac)2(H2O)2·0.5(C6H14)] (2) [La = 1,3-bis(1'-oxyl-3'-oxido-4',4',5',5'-tetramethyl-4,5-dihydro-1H-imidazol-2-y1)benzene; Lb = 1-(1'-oxyl-4',4',5',5'-tetramethylimidazolin-2-yl)-3-(1'-oxyl-3'-oxo-4',4',5',5'-tetramethylimidazolin-2-yl)benzene; hfac = hexafluoroacetylacetonato). Surprisingly, the compounds were not polymeric or clusters but, more interestingly, different ratio biradical-metal coordination compound cocrystals. The extensive intramolecular H-bonds are the cause of formation of the cocrystal structures by assembly in the two manganese(II) derivatives; and another factor is the halogen bonds between CF3 of hfac groups. Furthermore, three-dimensional supramolecular architectures were formed. The magnetic susceptibility of both compounds showed strong antiferromagnetic interactions involving the coordinated radical unit and the metal and lesser contribution from ferromagnetic interactions between the radical units. For compound 1, a good fit was obtained for g Mn = 2.08, g rad = 2.00 (fixed), J 1 = -294.3 cm-1, J 2 = 6.2 cm-1 and J 3 = 10.8 cm-1. A reasonable fit for compound 2 was obtained for g Mn = 2.04, g rad = 2.00 (fixed), J 1' = -273.4 cm-1 and J 2' = 8.6 cm-1.

6.
RSC Adv ; 12(18): 11047-11051, 2022 Apr 07.
Article in English | MEDLINE | ID: mdl-35425070

ABSTRACT

We report the synthesis and crystal structure of novel co-ligand phosphine/alkynyl protected Au nanoclusters, with composition [Au11(PPh3)8(C[triple bond, length as m-dash]CPh-CF3)2](SbF6) (1). The gold atoms in the cluster as a capped crown structure subtend C 3v symmetry with one deriving from a central icosahedron and 10 peripheral Au atoms, and all alkynides are exclusively σ coordination bonding. The mean core diameter is about 5.1 Å and the overall van der Waals diameter can be estimated to be 20.5 Å. The optical absorbance of 1 in solution reveals characteristic peaks at 384 and 426 nm and a shoulder between 450 and 550 nm.

7.
BMC Cancer ; 21(1): 1302, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34872514

ABSTRACT

BACKGROUND: Currently, no available coherent management protocol exists for pediatric cancers associated with pleural effusion, ascites, and pericardial effusion. This study aimed to retrospectively present our experience in treating pediatric cancer patients with pleural effusion, ascites, and pericardial effusion using interleukin-2 (IL-2) and dexamethasone (DEX) intracavitary injections. METHODS: Between January 1st, 2008 and December 31st, 2020, medical reports of patients diagnosed with solid tumors or lymphoma were checked to identify patients diagnosed with > 2 cm pleural effusion, and/or more than grade 1 ascites, and/or more than small pericardial effusion. Patients diagnosed with effusions and treated with IL-2 and DEX were identified as being in the effusion group. Meanwhile, patients with the same primary tumors and effusions but did not receive interleukin 2 and DEX injection were reviewed and classified as the control group. RESULTS: Forty patients with solid tumors and 66 patients with lymphoma were further diagnosed with pleural effusion, ascites, or pericardial effusion. A total of 85 patients received IL-2 and DEX injection while the remaining 21 did not. The Kaplan Meier analysis revealed a significant difference between the two groups, with p < 0.01 for event free survival (EFS) and p < 0.01 for overall survival (OS), both of which had p < 0.01. Hazard ratio was found to be 0.344 for OS and 0.352 for EFS. CONCLUSIONS: This retrospective study illustrates that thoracic, intraperitoneal, or pericardial intracavitary injection of DEX plus IL-2 can be an effective and safe treatment for pediatric cancers with pleural effusion, ascites, and pericardial effusion.


Subject(s)
Dexamethasone/therapeutic use , Interleukin-2/metabolism , Lymphoma/drug therapy , Pleural Effusion, Malignant/drug therapy , Child , Child, Preschool , Cohort Studies , Dexamethasone/pharmacology , Female , Humans , Male , Retrospective Studies
8.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Article in English | MEDLINE | ID: mdl-34846291

ABSTRACT

A Gram-stain-positive, non-motile and coccus-shaped bacterium, designated strain LNNU 331112T, was isolated from the composite rhizosphere soil of the halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze, which was collected in Xinjiang, north-west China. Growth occurred at 10-45 °C, pH 6.0-11.0 and in the presence of 0-10 % NaCl (w/v). Phylogenetic analysis based on the 16S rRNA gene sequence suggested that strain LNNU 331112T belonged to the genus Hoyosella and showed 95.6, 95.5 and 95.4 % sequence similarities to Hoyosella altamirensis DSM 45258T, Hoyosella subflava CGMCC 4.3532T and Hoyosella rhizosphaerae CGMCC 1.15478T, respectively. The estimated digital DNA-DNA hybridization relatedness values between strain LNNU 331112T and the type strains of H. altamirensis DSM 45258T, H. subflava CGMCC 4.3532T and H. rhizosphaerae CGMCC 1.15478T were 18.9, 19.3 and 18.3 %, respectively. The average nucleotide identity values between strain LNNU 331112T and H. altamirensis DSM 45258T, H. subflava CGMCC 4.3532T and H. rhizosphaerae CGMCC 1.15478T were 72.6, 72.7 and 72.3 %, respectively. The genome sequence of strain LNNU 331112T showed 69.0-72.3 % average amino acid identity values in comparison with the related genome sequences of three validly published Hoyosella species. The genome of strain LNNU 331112T was 3.47 Mb, with a DNA G+C content of 68.4 mol%. A total of 3182 genes were identified as protein-coding in strain LNNU 331112T. Genomic analysis revealed that a number of genes involved in osmotic pressure regulation, intracellular pH homeostasis and potassium (K+) uptake protein were found in strain LNNU 331112T. The predominant menaquinones were MK-8 (44.6 %) and MK-7 (55.4 %), which differentiated strain LNNU 331112T from other three recognized Hoyosella species. Major fatty acids (>10 %) were C17 : 1 ω8c (33.8 %), C16 : 0 (23.3 %), C17 : 0 (12.8 %) and summed feature 3 (12.9 %), which also clearly separated strain LNNU 331112T from three recognized Hoyosella species. The polar lipid profile of strain LNNU 331112T included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, one unidentified glycolipid, one unidentified phospholipid and two unidentified lipids. According to the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain LNNU 331112T is considered to represent a novel species of the genus Hoyosella, for which the name Hoyosella suaedae sp. nov. is proposed. The type strain is LNNU 331112T (=KCTC 39808T=CGMCC 1.17107T=DSM 103463T).


Subject(s)
Chenopodiaceae , Mycobacteriaceae/classification , Phylogeny , Rhizosphere , Soil Microbiology , Bacterial Typing Techniques , Base Composition , Chenopodiaceae/microbiology , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Mycobacteriaceae/isolation & purification , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
9.
Oxid Med Cell Longev ; 2021: 5040326, 2021.
Article in English | MEDLINE | ID: mdl-34257801

ABSTRACT

The function and mechanism underlying the suppression of human osteosarcoma cells by ginsenoside-Rg5 (Rg5) was investigated in the present study. MG-63, HOS, and U2OS cell proliferation was determined by MTT assay after Rg5 treatment for 24 h. Rg5 inhibited human osteosarcoma cell proliferation effectively in a dose-dependent manner. The range of effective inhibitory concentrations was 160-1280 nM. Annexin V-FITC and PI double-staining assay revealed that Rg5 induced human osteosarcoma cell apoptosis. Western blotting, qRT-PCR, and FACS experiments revealed that Rg5 inhibited human osteosarcoma cells via caspase-3 activity which was related to the LC3-mediated autophagy pathway. Rg5 decreased the phosphorylation of PI3K, Akt, and mTORC1 activation. In contrast, LC3-mediated autophagy and caspase-3 activity increased significantly. A PI3K/AKT stimulator, IGF-1, reversed Rg5-induced cell autophagy and apoptosis in MG-63 cells. Collectively, the current study demonstrated that Rg5 induced human osteosarcoma cell apoptosis through the LC3-mediated autophagy pathway. Under physiological conditions, activation of PI3K/AKT/mTORC1 inhibits LC3 activity and caspase-3-related cell apoptosis. However, Rg5 activated LC3 activity by inhibiting the activation of PI3K/AKT/mTORC1. The present study indicated that Rg5 could be a promising candidate as a chemotherapeutic agent against human osteosarcoma.


Subject(s)
Ginsenosides/therapeutic use , Osteosarcoma/drug therapy , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Apoptosis , Autophagy , Cell Line, Tumor , Cell Proliferation , Ginsenosides/pharmacology , Humans , Signal Transduction
10.
Exp Ther Med ; 22(2): 840, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34149886

ABSTRACT

Ginseng, a perennial plant belonging to genus Panax, has been widely used in traditional herbal medicine in East Asia and North America. Ginsenosides are the most important pharmacological component of ginseng. Variabilities in attached positions, inner and outer residues and types of sugar moieties may be associated with the specific pharmacological activities of each ginsenoside. Ginsenoside Rg5 (Rg5) is a minor ginsenoside synthesized during ginseng steaming treatment that exhibits superior pharmaceutical activity compared with major ginsenosides. With high safety and various biological functions, Rg5 may act as a potential therapeutic candidate for diverse diseases. To date, there have been no systematic studies on the activity of Rg5. Therefore, in this review, all available literature was reviewed and discussed to facilitate further research on Rg5.

11.
Clin Rheumatol ; 40(2): 601-612, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32613392

ABSTRACT

OBJECTIVE: This paper is aimed at investigating the clinical characteristics of primary Sjogren's syndrome (pSS) with lymphocytic interstitial pneumonia (LIP). METHODS: The demographic data, clinical manifestations, laboratory and radiological findings, treatment, and prognosis from 15 cases of pSS-LIP patients were retrospectively analyzed. The data were compared with t test, χ 2 test, and Pearson/Spearman correlation analysis. RESULTS: (1) Fifteen cases of patients with pSS-LIP are all females (100%). Compared with pSS with interstitial lung disease(pSS-ILD) patients, the incidence of dry cough, dental caries is higher in pSS-LIP patients. The incidence of shortness of breath, weight loss, and crackles is lower in pSS-LIP patients than that of pSS-ILD patients. (2) Compared with pSS-ILD patients, pSS-LIP patients had higher percentage of patients with ANA, anti-SSA52KD antibody, anti-SSA60KD antibody, and anti-SSB antibody, and the higher concentration of serum globulin. (3) Compared with pSS-ILD patients, the frequency of obstructive ventilation dysfunction is significantly higher and the frequency of diffusion dysfunction is significantly lower in pSS-LIP patients. (4) The most frequent HRCT findings in patients with pSS-LIP is cysts (100%), followed by ground-glass opacities (73.3%), nodular shadow (73.3%) among the pSS-LIP patients. Compared with PSS-ILD patients, the incidence of pulmonary nodule shadow is significantly higher in PSS-LIP patients, while that of grid shadow was significantly lower. (5) Compared with the baseline, the sum of the number, maximum diameter, and diameter of cysts in three levels of pSS-LIP patients showed an increasing trend after treatment. (6) Correlation analysis: The changes of ground-glass opacities were positively correlated with using GC or not, and those were negatively correlated with the dose of GC treatment. Besides, there is a positive correlation between the annual change rate of the maximum diameter of cysts (△Ømax1/t) and the use of CTX; there is a positive correlation between the annual change rate of the total diameter of cysts (△Øsum1/t) and the use of CTX. CONCLUSION: To the patients of pSS-LIP, female were more common than male, and the onset of LIP was usually more insidious. Hyperglobulinemia and anti-SSA antibody were more prominent in patients with pSS-LIP. Pulmonary function showed the higher rate of obstructive ventilation dysfunction and the lower rate of diffusion dysfunction. The appearance of ground-glass opacities in pSS-LIP patients suggests that the infiltration of inflammatory cells increases, which may cause airway compression, the expansion of terminal bronchioles, and the formation of cysts. The more ground-glass opacities appear earlier, and the more appearance of new cysts later. Therapy with glucocorticoid may be effective on the ground-glass opacity during acute stage, and therapy with cyclophosphamide may be effective on the cysts during chronic stage. The heavier ground-glass opacity is at baseline, the more likely it will recur during maintenance treatment. So follow-up closely is needed. Key Points • It is the first clinical study with more cases of patients with pSS-LIP. • Female and hyperglobulinemia and anti-SSA antibody were more prominent in patients with pSS-LIP. • Pulmonary function showed the higher rate of obstructive ventilation dysfunction and the lower rate of diffusion dysfunction. • Therapy with glucocorticoid may be effective on the ground-glass opacity during acute stage, and therapy with cyclophosphamide may be effective on the cysts during chronic stage.


Subject(s)
Dental Caries , Lung Diseases, Interstitial , Sjogren's Syndrome , Female , Humans , Lung/diagnostic imaging , Lung Diseases, Interstitial/diagnostic imaging , Male , Retrospective Studies , Sjogren's Syndrome/complications
12.
Ying Yong Sheng Tai Xue Bao ; 31(9): 2849-2856, 2020 Sep 15.
Article in Chinese | MEDLINE | ID: mdl-33345485

ABSTRACT

Soil nitrogen cycling in forests may be accelerated or inhibited by global warming, with consequences on forest productivity. Such an impact will be more complicated with extending period of warming. We examined the effects of warming on soil inorganic nitrogen content in the young and mature Cunninghamia lanceolata plantations. Warming was simulated by means of soil cable warming, simulating a future climate change scenario of 4 ℃ warming. The results showed that after three years warming, both total soil inorganic nitrogen and ammonium contents in the young and mature plantations were significantly reduced. The sharp decline occurred in the young plantation, with soil ammonium content in 0-10, 10-20, 20-40, 40-60 cm soil layers decreased by 32.1%, 37.1%, 20.8% and 19.9%, respectively. Dissolved organic nitrogen was reduced and N2O emission was accelerated in the both plantations. The main reasons for the reduction of soil inorganic nitrogen concentration were lower input of organic nitrogen substrate and higher gaseous nitrogen loss. The decrease in soil organic nitrogen substrate and increase in gaseous nitrogen emissions in the young plantation were larger than those in the mature plantation, indicating that soils in the young plantation were more sensitive to increasing temperature. The 3-year warming decreased soil inorganic nitrogen contents in the two C. lanceolata plantations, which might negatively affect productivity of the C. lanceolata plantations in subtropic China.


Subject(s)
Cunninghamia , Carbon/analysis , China , Nitrogen/analysis , Nitrogen Cycle , Soil
13.
Viruses ; 12(9)2020 09 20.
Article in English | MEDLINE | ID: mdl-32962247

ABSTRACT

Marek's disease (MD) is an infectious malignant T-cell lymphoma proliferative disease caused by Marek's disease virus (MDV). In recent years, the emergence of very virulent (vv) and/or very virulent plus (vv +) strains of MDV in the field has been suggested as one of the causes of vaccination failure. The pathogenicity of the MDV strain GX18NNM4, isolated from a clinical outbreak in a broiler breeder flock that was vaccinated with CVI988/Rispens, was investigated. In the vaccination-challenge test, GX18NNM4 was able to break through the protections provided by the vaccines CVI988 and 814. It also significantly reduced body weight gain and caused marked gross lesions and a large area of infiltration of neoplastic lymphocyte cells in the heart, liver, pancreas, etc. of the infected birds. In addition, the expressions of programmed death 1 (PD-1) and its ligand, programmed death ligand 1 (PD-L1), in the spleens and cecal tonsils (CTs) of the unvaccinated challenged birds were significantly increased compared to those in the vaccinated challenged birds, indicating that the PD-1/PD-L1 pathway is related to immune evasion mechanisms. The results showed that the GX18NNM4 strain could cause severe immunosuppression and significantly decrease the protections provided by the current commercial vaccines, thus showing GX18NNM4 to be a vv + MDV strain.


Subject(s)
Herpesvirus 2, Gallid/pathogenicity , Marek Disease Vaccines/immunology , Marek Disease/prevention & control , Animals , B7-H1 Antigen/metabolism , Chickens/virology , Immune Tolerance , Immunosuppression Therapy , Marek Disease/pathology , Marek Disease/virology , Poultry Diseases/virology , Programmed Cell Death 1 Receptor/metabolism , Spleen/immunology , Vaccination/veterinary , Viral Load
14.
Ying Yong Sheng Tai Xue Bao ; 31(2): 515-523, 2020 Feb.
Article in Chinese | MEDLINE | ID: mdl-32476345

ABSTRACT

The fertilizer and shading management of Coffea arabica in dry-hot area is extensive, resulting in lower yield and fertilizer utilization efficiency. A field experiment was carried out to find the coupling mode of shading and fertilizer for fertilizer-saving and high yield of C. arabica in dry-hot region. Four shading levels (100% NR, 75% NR, 60% NR, 45% NR, NR was natural radiation) and four fertilizer levels (No fertilization and 666.67, 1000, 1333.33 kg·hm-2) were set to examine the effects of different radiations and fertilizer treatments on canopy structure, yield, ferti-lizer use efficiency, soil nutrient content and microbial biomass carbon of C. arabica. The results showed that canopy structure, yield, fertilizer use efficiency, soil nutrient content and microbial biomass carbon were significantly affected by shading and fertilizer treatments. Soil nutrient content and microbial biomass carbon decreased with the increases of shading levels. Soil nutrient content increased with the increases of fertilizer application, while microbial biomass carbon increased first and then decreased, with a peak at the rate of 1000 kg·hm-2(200.30 mg·kg-1). Shading and fertilizer had significant effects on the canopy structure including leaf area index and openness. There were significant negative correlations of leaf area index with openness, gap fraction, total fixed-point factor and total radiation under canopy. Results of response surface analysis and spatial analysis showed that the combination of shading level and fertilizer application were 80% NR and 666.67 kg·hm-2, 79% NR and 1286.81 kg·hm-2, 79% NR and 967.74 kg·hm-2, 82% NR and 1075.27 kg·hm-2, respectively, when partial fertilizer productivity, yield, fertilizer agronomic efficiency and yield increase of fertilizer reached the maximum. The ranges of shading and fertilizer were 68%-77% NR and 946.24-1178.79 kg·hm-2 when the yield, agronomic efficiency and yield increasing rate by fertilizer reached 80% of the maximum value. In this experiment, the optimum combination of shading level and fertilizer application was 75% NR and 1000 kg·hm-2.


Subject(s)
Coffea , Fertilizers , Agriculture , Biomass , China , Nitrogen , Soil
15.
World J Stem Cells ; 12(3): 188-202, 2020 Mar 26.
Article in English | MEDLINE | ID: mdl-32266051

ABSTRACT

In steady state, the intestinal epithelium forms an important part of the gut barrier to defend against luminal bacterial attack. However, the intestinal epithelium is compromised by ionizing irradiation due to its inherent self-renewing capacity. In this process, small intestinal bacterial overgrowth is a critical event that reciprocally alters the immune milieu. In other words, intestinal bacterial dysbiosis induces inflammation in response to intestinal injuries, thus influencing the repair process of irradiated lesions. In fact, it is accepted that commensal bacteria can generally enhance the host radiation sensitivity. To address the determination of radiation sensitivity, we hypothesize that Paneth cells press a critical "button" because these cells are central to intestinal health and disease by using their peptides, which are responsible for controlling stem cell development in the small intestine and luminal bacterial diversity. Herein, the most important question is whether Paneth cells alter their secretion profiles in the situation of ionizing irradiation. On this basis, the tolerance of Paneth cells to ionizing radiation and related mechanisms by which radiation affects Paneth cell survival and death will be discussed in this review. We hope that the relevant results will be helpful in developing new approaches against radiation enteropathy.

16.
Chin Med J (Engl) ; 132(20): 2402-2407, 2019 Oct 20.
Article in English | MEDLINE | ID: mdl-31567476

ABSTRACT

BACKGROUND: Primary spontaneous pneumothorax (PSP) is a common manifestation of Birt-Hogg-Dubé (BHD) syndrome, which is an autosomal dominant disorder caused by mutation of the folliculin (FLCN) gene. This study was established to investigate the mutation of the FLCN gene and the phenotype in a family with PSP. METHODS: We investigated the clinical and genetic characteristics of a large Chinese family with recurrent spontaneous pneumothorax. Genetic testing was performed by Sanger sequencing of the coding exons (4-14 exons) of the FLCN gene. RESULTS: Among ten affected members in a multi-generational PSP kindred, with a total of 18 episodes of spontaneous pneumothorax, the median age for the initial onset of pneumothorax was 42.5 years (interquartile range: 28.8-57.2 years). Chest computed tomography scan of the proband showed pulmonary cysts and pneumothorax. A novel nonsense mutation (c.1273C>T) in exon 11 of FLCN gene that leads to a pre-mature stop codon (p.Gln425*) was identified in the family. The genetic analysis confirmed the diagnosis of BHD syndrome in this family in the absence of skin lesions or renal tumors. CONCLUSIONS: A novel nonsense mutation of FLCN gene was found in a large family with PSP in China. Our results expand the mutational spectrum of FLCN gene in patients with BHD syndrome.


Subject(s)
Birt-Hogg-Dube Syndrome/genetics , Codon, Nonsense , Pneumothorax/genetics , Proto-Oncogene Proteins/genetics , Tumor Suppressor Proteins/genetics , Adult , Female , Genetic Testing , Humans , Male , Middle Aged , Recurrence
17.
J Cell Biochem ; 120(5): 7635-7648, 2019 May.
Article in English | MEDLINE | ID: mdl-30450663

ABSTRACT

Myocardial ischemia-reperfusion injury (MIRI) is a major cause of cardiovascular disease, leading to mortality and disability associated with coronary occlusion worldwide. A correlation of mammalian target of rapamycin (mTOR)/nuclear factor-kappa B (NF-κB) signaling pathway has been observed with brain damage resulting from myocardial ischemia. Therefore, by establishing MIRI rat model, this study aimed to explore whether ring finger protein 182 (RNF182) regulates the mTOR signaling pathway affecting MIRI. Initially, MIRI rat model was successfully established, followed by either treatment of shRNF182 or phosphoesterase (PITE) (inhibitor of the mTOR signaling pathway). Then, the serum levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA), left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), left ventricular systolic pressure (LVSP), and left ventricular end-diastolic pressure (LVEDP) were determined, followed by detection of myocardial infarct sizes and myocardial cell apoptosis. Moreover, the levels of related genes/proteins were determined to further determine the mechanisms of RNF182 in MIRI. First, RNF182 was upregulated in MIRI. Another key observation of this study was that rats with shRNF182 presented with downregulated SOD, GSH-Px, and MDA in serum, accompanied by decreased levels of LVEF, LVFS, LVSP, and LVEDP. In addition, both reduced myocardial infarct sizes and apoptosis of myocardial cells were observed after silencing RNF182. Furthermore, silencing of the RNF182 was observed to downregulate Bcl 2-associated X and cysteine proteinase 3 but upregulate mTOR, ribosome protein subunit 6 kinase 1, eukaryotic elongation factor 2, and B-cell lymphoma-2. Importantly, the effects of RNF182 silencing were reversed after PITE treatment. In conclusion, our study demonstrates that RNF182 silencing can prevent ventricular remodeling in rats after MIRI by activating the mTOR signaling pathway.

18.
Am J Physiol Lung Cell Mol Physiol ; 312(5): L669-L677, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28213472

ABSTRACT

ß2-Microglobulin (ß2M), the light chain of the major histocompatibility complex class I (MHC I), has been identified as a proaging factor and is involved in the pathogenesis of neurodegenerative disorders by driving cognitive and regenerative impairments. However, little attention has focused on the effect of ß2M in the development of lung emphysema. Here, we found that concentrations of ß2M in plasma were significantly elevated in patients with lung emphysema than those in normal control subjects (1.89 ± 0.12 vs. 1.42 ± 0.06 mg/l, P < 0.01). Moreover, the expression of ß2M was significantly higher in lung tissue of emphysema (39.90 ± 1.97 vs. 23.94 ± 2.11%, P < 0.01). Immunofluorescence showed that ß2M was mainly expressed in prosurfactant protein C-positive (pro-SPC+) alveolar epithelial cells and CD14+ macrophages. Exposure to recombinant human ß2M and cigarette smoke extract (CSE) in vitro enhanced cellular senescence and inhibited proliferation of A549 cells, which was partially reversed by the presence of anti-ß2M antibody. However, anti-ß2M antibody did not attenuate the elevated production of IL-1ß, IL-6, and TNF-α in A549 cells that were exposed to CSE. Immunofluorescence showed that colocalization of ß2M, and the hemochromatosis gene (HFE) protein was observed on A549 cells. These data suggest ß2M might participate in the development of lung emphysema through induction of lung epithelial cell senescence and inhibition.


Subject(s)
Cellular Senescence , Epithelial Cells/metabolism , Epithelial Cells/pathology , Lung/pathology , Pulmonary Emphysema/metabolism , Pulmonary Emphysema/pathology , beta 2-Microglobulin/metabolism , A549 Cells , Antibodies/pharmacology , Cell Proliferation/drug effects , Cellular Senescence/drug effects , Demography , Epithelial Cells/drug effects , Female , Humans , Male , Middle Aged , Phenotype , Pulmonary Emphysema/blood , Smoking/adverse effects , beta 2-Microglobulin/blood
19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 34(6): 590-4, 2012 Dec.
Article in Chinese | MEDLINE | ID: mdl-23286404

ABSTRACT

OBJECTIVE: To study the expressions and clinical significances of p-extracellular regulated kinase(P-ERK)1/2 and matrix metalloproteinase-9(MMP-9)in cervical squamous cell carcinoma. METHODS: The expressions of P-ERK1/2 and MMP-9 in 30 cases with chronic cervicitis, 45 cases with cervical intraepithelial neoplasia (CIN), and 58 cases with cervical squamous cell carcinoma were detected by immunohistochemical method. RESULTS: The positive rates of P-ERK1/2 and MMP-9 in chronic cervicitis, CIN, and cervical squamous cell carcinoma were 0 and 0, 28.9% and 24.4%, 77.6% and 65.5%, respectively, showing significant differences among these three groups (χ(2)= 54.393,p=0.003;χ(2)=40.968,p=0.005). The positive rates of P-ERK1/2 and MMP-9 in patients at clinical stages 2-3, at G3, with lymphatic metastasis, or with a tumor diameter greater than 4 cm were significantly higher than those at clinical stage 1(p=0.015,p=0.002), at G1-G2(p=0.013,p=0.017), without lymphatic metastasis (p=0.017,p=0.021), or with a tumor diameter less or equal than 4 cm in cervical squamous cell carcinoma(p=0.008,p=0.004). There was a positive correlation between P-ERK1/2 and MMP-9 in cervical squamous cell carcinoma (χ(2)=8.955,p=0.006). CONCLUSIONS: The expressions of P-ERK1/2 and MMP-9 increase gradually with the progression of cervical squamous cell carcinoma. The over expressions of P-ERK1/2 and MMP-9 may promote the infiltration of cervical squamous cell carcinoma and lymphatic metastasis, druing which these two enzymes may exert their effects in a synergistic manner.


Subject(s)
Carcinoma, Squamous Cell/enzymology , Matrix Metalloproteinase 9/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Uterine Cervical Neoplasms/enzymology , Carcinoma, Squamous Cell/pathology , Female , Humans , Mitogen-Activated Protein Kinase 1/metabolism , Uterine Cervical Neoplasms/pathology
20.
Hum Vaccin ; 6(6): 462-6, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20519939

ABSTRACT

A good immunogen was developed as an effective recombinant vaccine candidate that protected mice against botulinum neurotoxin serotype B (BoNT/B) intoxication. The Hc fragment of Clostridium botulinum neurotoxin type B (rBoNT/B-Hc) was cloned into the bacterial expression vector pQE-30, and the resulting vector was successfully expressed in the Escherichia coli M15 strain. The purified rBoNT/B-Hc protein was used to vaccinate mice and evaluate their survival against challenge with native BoNT/B. The mice that received three subcutaneous injections of rBoNT/B-Hc immunogen doses ranging from 0.25 to 6.25 µg mixed with Freund's adjuvant were completely protected against an intraperitoneal (i.p.) administration of 10,000 50% lethal doses (LD50) of BoNT/B. A dose response was observed in both the ELISA antibody titers and protective efficacy with increasing dose of immunogen. The work presented here demonstrates that the purified rBoNT/B-Hc was a highly effective immunogen and able to protect against a high-dose neurotoxin challenge.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Vaccines/immunology , Botulinum Toxins/immunology , Botulism/prevention & control , Clostridium botulinum type B/immunology , Animals , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/genetics , Botulinum Toxins/administration & dosage , Botulinum Toxins/genetics , Botulinum Toxins, Type A , Botulism/blood , Botulism/immunology , Dose-Response Relationship, Immunologic , Escherichia coli/genetics , Escherichia coli/metabolism , Female , Injections, Subcutaneous , Mice , Mice, Inbred BALB C , Peptide Fragments/administration & dosage , Peptide Fragments/genetics , Peptide Fragments/immunology , Protein Engineering , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Vaccination , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology
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